The Pacman Nebula is a bright Ha and O3 emission nebula in Cassiopeia. The image below was captured over three nights in August.
For this image I used the Svbony SV220 dual band filter with the Touptek AR533C. Integration time was about 12hrs (148 x 300s). The OTA and mount were my 70mm EDT-F and HEQ5pro.
I processed the stars separately from the nebula before recombining them. Star colours are little off but more natural than unprocessed or pure white. I used the Pixinsight SCNR tool on the normal and inverted image to remove green and purple tints leaving just reddish and bluish stars.
The whole nebula is strongly Ha emitting but by exaggerating other wavelengths we can show the presence of O3 nebula. To do this the image was processed using an SHO script and various colour masks were used to highlight mainly Ha (Golden) areas and with blue areas indicating Oxygen 3 too. Generalised Hyperbolic stretch was used to exaggerate the light cloud structure and lowlight the darker regions.